The act of immersing or washing. In Holy Scripture it also signifies, figuratively, great suffering, e.g., Christ’s Passion (Luke 12). It is the “first” sacrament, or sacrament of initiation and regeneration, the “door of the Church.” Defined theologically, it is a sacrament, instituted by Christ, in which by the invocation of the Holy Trinity and external ablution with water one becomes spiritually regenerated and a disciple of Christ. SaintThomas Aquinas says it is the “external ablution of the body performed with the prescribed form of words.” The Sacrament of Baptism is absolutely necessary for salvation, because all are subject to original sin: wherefore Christ’s words to Nicodemus,

Unless a man be born again of water and the Holy Ghost, he cannot enter into the kingdom of God. (John 3)

regeneration and remission of original sin (and actual if necessary), as well as punishment due to sin, and infusion of sanctifying grace (with its gifts). Baptism is administered by pouring water on the head of the candidate, saying at the same time

I baptize thee, in the name of the Father, and of the Son, and of the Holy Ghost.

with the intention of Christ or His Church. The water must flow over the skin. These essentials are apart from the beautiful requirements of the Church for solemn Baptism. Infusion (pouring), immersion, and aspersion (sprinkling) are equally valid. The present ritual of the Latin Church allows for the first two, favoring infusion by the law of custom. Baptism of desire (flaminis) and of blood (sanguinis) are called such analogically, in that they supply the remission of sin and the regenerative grace, but not the character; the former presupposes perfect charity or love of God (therefore implicitly the desire for the sacrament), while the latter is simply martyrdom for the sake of Christ or His Church. Without the Sacrament of Baptism or martyrdom it is commonly taught that infants cannot attain to the enjoyment of the Beatific Vision.